The technology disclosed herein generally relates to Computed Tomography (CT). More specifically, the technology disclosed herein relates to systems and methods for metal artifact reduction in a CT image.
Computed tomography imaging uses X-rays to generate CT images of a subject (e.g., a human patient, a phantom object, and the like). Often, the subject includes metal objects or other high-density objects, for example, metal prostheses, dental implants, surgical clips, and the like. Typically, the presence of a metal object in the subject results in degradation in the quality of the CT images since the metal object has strong absorption of X-rays, causing metal artifacts such as streaks and shadings in the CT images that obscure other portions of the subject. For example, a titanium hip in a human patient may cause photon starvation and lead to metal artifacts in a CT image of the human patient. In such an example, the metal artifacts limit the assessment of soft tissue and skeletal portions surrounding the metallic hip in the CT image and may lead to a misdiagnosis of the subject. Prior methods of metal artifact reduction often include corrections to the corrupted image data based on assumptions and approximations. However, such prior methods based on assumptions and approximations tend to introduce new artifacts and hence fail to generate CT images of satisfactory quality.